Steps to reproduce:
1) place a block. On one side, place a repeater facing away from the block. On the other, place a redstone dust.
2) Redirect the dust with a piston, target block, or other component that redirects dust such that it does not point into the block behind the repeater.
3) power the dust.

Expected result: repeater stays unlit.

Observed result: Repeater transmits signal.